Mirrors Optics

…translucent, nonliving envelope called a pellicle. In nonmoving (sessile) coelenterates, such as coral, whose colonies attain great size, it is achieved by dead structures, both internal and external, which form supporting axes. In the many groups of animals that can move, it is achieved either by external structures known as…

45degree mirror

… wall and have a flexible pellicle (envelope) that allows them to change shape. Though they are photosynthetic, most species can also feed heterotrophically (on other organisms) and absorb food directly through the cell surface via phagocytosis (in which the cell membrane entraps food particles in a vacuole for digestion). Food…

Flatmirror

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Students experiment to find that when two plane mirrors are placed at a 90-degree angle, the image of the first mirror is reflected in the second mirror so that the reversed mirror image is reversed again, and the viewer sees a true image. Reflection of Light With Two Plane Mirrors – Double Mirrors Placed at a 90-Degree Angle  [113KB PDF file] This activity is part of the Optics, Light, Color, and their uses Educator Guide.

…known as kineties, on the pellicle (cell covering), but they may fuse together near the cytostome (cell mouth) of some species to form membranelles or undulating membranes (various sheetlike or fan-shaped groupings of cilia); elsewhere on the pellicle, cilia may form limblike tufts called cirri. Most ciliates have a flexible…